1. Field of the Invention
The invention relates to an apparatus for manufacturing coil screens with at least one winding device, arranged above a working surface, for the production of coils and a depositing device with which the coils can be deposited on the working surface.
2. Discussion of Background Information
In the production of what are referred to as spiral screens, coils of helically wound plastic wires are deposited next to one another on a working surface and brought into engagement with one another. A fixing wire made of plastic is then inserted in the region of overlap between adjacent coils. The coils connected to one another in such a manner are typically moved transverse to their longitudinal direction by at least one coil width in order to make room for additional coils.
An apparatus of the type named at the outset is known, e.g., from DE 10 2007 052 594 B4 and its family member U.S. Patent Publication No. 2010/0287775, the disclosures of which are expressly incorporated by reference herein it their entireties. In this known apparatus, a winding device is arranged above the working surface in order to produce the coils on the spot, as it were. In this manner, a multi-stage process is avoided in which the coils must first be produced and then stored intermediately before they can be removed from the intermediate storage and deposited on the working surface. This two-stage method involves a considerable risk in that the coils can become knotted or entangled with one another, which hinders the removal from the intermediate storage and can cause damage.
In the known apparatus from DE 10 2007 052 594 B4 and its family member U.S. Patent Publication No. 2010/0287775, the depositing device is moved together with the winding device over the working surface and a length of one coil is thereby deposited on the working surface. The winding device is subsequently moved back to the starting point again with the depositing device, in order to produce the next coil and deposit it on the working surface. It is also possible to simultaneously use multiple winding devices and move them over the working surface. During the return movement of the winding device to the starting point, the depositing process is interrupted. A synchronous interruption of the coil production is, in terms of process technology, virtually impossible and would result in a considerable loss in quality of the coils produced. However, the quality of a coil screen made up of the coils depends, among other things, on the quality of the coils produced.